This application claims the priority of the Swiss patent application No. 1978/99, filed on Oct. 29th, 1999, the disclosure of which is incorporated herein by reference in its entirely.
The present invention relates to double clipping apparatuses according to the preambles of the claims 1, 20 and 21 and to a method for forming clipped sausages according to the preamble of claim 26.
Double clipping apparatuses are used in butcher""s shops for the production of sausages from filled artificial or natural casings. For doing so, at one position of the filled casing that later is located between two sausages, the casing is gathered and then the constriction obtained is voided. After that the gathered and voided section is pinched off by installing two metal clips with a distance between them and is, where appropriate, cut between the clips, whereby the ends of the sausages are formed. Depending on the type of sausage, the size and the casing used for the sausages, the desired distance between the clips may be different. Such apparatus are also used for closing other tubular packagings.
There are known double clipping apparatus which clip distance can be adjusted to the particular product by converting the apparatus. This conversion, however, is time-consuming, which means a corresponding production loss, and necessitates additional components, wherefore often a single, however for many products too large clip distance is used, causing in consequence that an unnecessary amount of casing material is consumed.
Hence, it is a general object of the invention to provide double clipping apparatuses and a method which do not have the before mentioned disadvantages.
Now, in order to implement these and still further objects of the invention, which will become more readily apparent as the description proceeds, the double clipping apparatus for forming sausages from a filled sausage type packaging or a filled casing by forming gathered and voided sections and installing in each of said sections at a time two clips at a distance from each other, is manifested by the features that it comprises a variable adjuster defining said distance.
Another aspect of the invention is a double clipping apparatus for forming sausages from filled tubular packagings or filled casings by forming gathered and voided sections and installing in each of said sections at a time two clips at a distance from each other, wherein said distance is manually or automatically, e.g. in dependence on one or several production-parameters, adjustable during operation of said apparatus.
A further aspect of the invention is a double clipping apparatus, for forming sausages with clipped ends from a filled casing by gathering and voiding sections of said casing and installing in each of said sections at a time two clips at a distance from each other that each form the end of a different sausage, wherein said distance is adjustable, without an exchange of components, by means of a variable adjuster defining said distance.
While sausage type packagings resp. tubular packagings are used to form sausages from all type of pasty or liquid materials (food and non-food), artificial or natural casings are used to form sausages from minced or otherwise processed meat.
All of the double clipping apparatuses as per the invention are designed in such a way, that the distance between the clips is adjustable without an exchange of components and the variable adjuster mentioned before is a component of the double clipping apparatus that can be adjusted without being taken away from the double clipping apparatus. This way, the clip-distance can be adjusted quickly and cost-effective, resp. can be adapted to the respectively produced product (sausage type and sausage size) and specific operating modes become possible, which have not been executable with the previous apparatuses.
Preferably, the clip distance is adjusted through a movement of at least one of the clip-channels relative to the other clip-channel, e.g. through a displacement motion for which preferably a controllable or a closed loop controllable movement means is provided, like e.g. a pneumatic actuating means, a hydraulic cylinder assembly, a spindle drive or a linear motor assembly.
Preferably, the clip-distance is adjustable during operation. This results in the advantage, that it can be used as a control-parameter for further production parameters.
In a preferred embodiment of the invention the clip-distance can be adjusted in stepless manner, in another embodiment it can be adjusted in steps.
Preferably, the adjustment of the clip-distance can be done manually. It is also of advantage, if it is automatically adjustable in dependence on one or several production parameters. By this, there is the possibility to let the clip-distance automatically be adjusted through a production control system, which results in a considerable ease when having a flexible production with a multitude of different products.
A preferred embodiment comprises actuating cylinders for the adjustment of the clip-distance in steps, preferably pneumatic cylinders.
Beside a product-specific adjustment of the clip-distance, it can moreover be desired to use it as a variable correction parameter in the running production process, for example for the label positioning in a production with packaging that carries customer labels, in particular sausages. The packaging resp. casings used in this case are printed in fixed distances with labels, which most times include the type of sausage and/or the company logo. The distances between the labels normally correspond with the theoretical length of the sausage. In order to achieve a uniform appearance of the sausages and to have the full information of the labels available on each sausage, it is desired that the label at each sausage is arranged in the same position between the clipped sausage ends. In case the clipping is done with fixed machine parameters, the label position will, due to tolerances, drift on the clipped sausages. In case a specific position of the labels on the end product has to be ensured, this position or the position of an auxiliary marking arranged in fixed distances to the labels has to be monitored and, if necessary, be corrected.
Therefore a preferred embodiment of the double clipping apparatus comprises at least one sensor for sensing markings arranged on the casing and an analysing and control electronics for controlling the clip-distance in dependence on the output signals of the sensor.
Preferably, the sensor and the analysing and control electronics are designed in such way, that they enable a determination of the position of a marking arranged on the casing relative to a point that is, in longitudinal direction of the casing, fixed relative to the double clipping apparatus, for example fixed relative to a clip-channel or to a clip tool. By this, the position of the marking with respect to the clips for the readily clipped sausage can be calculated and, if necessary, be corrected through a selective change of the clip-distance.
In a further embodiment the sensor and the analysing and control electronics are designed in such way, that in a static state, e.g. in a state without relative movement between double clip apparatus and casing, which for gathering, voiding and clipping is common, they enable the determination of the position of a marking arranged on the casing relative to such a fixed point. This can be done through all thinkable combinations of sensors and markings, which are suitable to determine their relative position to each other in a static state, like e.g. simple geometric markings in combination with one-dimensional line scanners or two-dimensional picture patterns sensors or through markings which show a position coding that changes over their extent, e.g. in the form of colour and/or brightness graduations, in combination with one or several of sensors that are sensible to these codings, like e.g. colour brightness sensors.
It is also preferred that the double clipping apparatus is designed for the determination of the position of a marking arranged on the casing in the voided section between two clipped sausages relative to a point that is, in longitudinal direction of the casing, fixed relative to the double clipping apparatus. Especially in the case that the markings used for the determination of the position are auxiliary markings, which shall not appear on the ready product, this is of advantage.
Furthermore it is desirable that the double clipping apparatus is designed in such way, that it can use an external signal for the triggering of the clipping action. By this, there is the possibility to synchronise the cycle of the double clipping apparatus with the one of another machine, e.g. a sausage filling-machine that is superposed in the production process.
It is in particular advantageous if the double clipping apparatus is used for the manufacture of sausages with labels located in a defined position between the clipped ends from a pre-printed casing.
A final aspect of the invention is a method for forming clipped sausages comprising the steps of:
a) feeding a filled casing with pre-printed labels through a double clipping apparatus;
b) determining a location of said labels on said casing; and
c) applying, in said double clipping apparatus, a pair of clips between two consecutive sausages for separating said consecutive sausages,
wherein a distance between said clips is adjusted depending on said location in order to maintain a pre-defined distance between said clips and said labels.
By continuously adjusting the clip distances in dependence on the determined actual location of said labels, a proper positioning of the labels on each of the sausages produced by this method can be achieved and can be maintained in an easy and reliable way.